Mankiw is a conservative – former Bush economic advisor and later a Romney advisor. While I get his point about the role conservatives could play in a carbon tax scheme, that seems to be tied to doing a revenue-neutral proposal – heaven forbid those liberals get their hands on more money with which to expand government! For those of us not in the inner circles of either movement, the question may be a bit different. I wrote earlier about the need to essentially do away with subterranean carbon fuel sources. If that’s the case, should extra revenues from a carbon tax go towards new programs to advance that goal? Global warming is likely to be horrendously expensive – what would it cost to relocate even part of the 40% of the American population that lives in coastal counties (per the map/demographic post a few days ago)? With the principle that it’s almost always cheaper to handle a problem before it occurs than after it hits, would we be smarter to use new funds in a preventative program or to go with revenue neutrality and kick the can down the road for others to handle?